Cocoa butter is an important ingredient of chocolate, but is frequently in relatively short supply. There have been many attempts to find a substitute or equivalent hard butter composition which can be blended with cocoa butter or used in place of cocoa butter.
The present invention particularly relates to an improved cocoa butter equivalent comprising a blend of refined, fractionated sal fat and a mid-fraction of palm oil.
Cocoa butter possesses a unique triglyceride structure which is not found in other fats. It consists of three major triglyceride groups, namely, POP, SOS, and POS, where P equals the palmitic acid, S equals the stearic acid, and O equals the oleic acid radicals positioned in 1-2-3 order on the esterified glycerine residue. These three triglycerides comprise nearly 80% of all the available glycerides in cocoa butter. Also, these particular triglycerides and their unique symmetrical saturated-unsaturated-saturated fatty acid arrangement contribute to cocoa butter's melting and solidification properties. Cocoa butter rapidly melts at body temperature, yet is remarkably hard at ambient conditions. It is for this reason that confectionery coatings containing fats other than cocoa butter often tend to exhibit poor functional quality while allowing for some cost savings. These cocoa butter substitute fats, called hard butters, are generally designed to replace specific portions of added cocoa butter in confectionery coatings. They, therefore, must have compatibility with various levels of cocoa butter if the desired quality is to be obtained. Generally, the more similar the hard butter is in triglyceride structure to cocoa butter, the more it can replace cocoa butter in confectionery applications without detrimental effects.
U.S. Pat. No. 2,975,060 (believed to be the equivalent of British Pat. No. 827,172) describes a cocoa butter equivalent comprising palm oil fraction rich in POP triglycerides, blended with Illipe Butter (Shorea stenoptera) as a source of SOS and POS triglycerides. When combined, these two component fats exhibit similar physico-chemical characteristics to cocoa butter, and as a result, compatibility with cocoa butter is said to be achieved at a broad range of admixture levels. The product of this patent is marketed by Unilever Ltd. under the trademark "Coberine". The Illipe Butter component, however, is not readily available on the market, making it necessary for manufacturers to search for other components for hard butter equivalents.
The fractionation of palm oil to yield POP-rich mid-fractions is well documented and is in practice by several palm oil manufacturers. For instance, the above mentioned U.S. Pat. No. 2,975,060 describes such fractional crystallization. However, it is generally felt that this material by itself is not useful as a cocoa butter equivalent.
In the U.S. Pat. No. 2,975,060 patent, one fractionation procedure disclosed involves obtaining a filter cake product from an acetone solvent solution of refined, deodorized palm oil of IV 53.4, at about 6.5.degree. C., and then obtaining from such filter cake a filtrate of IV 33.6 by a second fractionation at about 26.degree. C. The only data given in the patent on the product are dilatation values at several temperatures, plus yield and IV (Iodine Value).
In Indian Pat. No. 129,348, accepted Mar. 23, 1972, there is described a method for the preparation of a cocoa butter substitute comprising a blend of a mid-fraction of palm oil with a fraction of sal fat, the latter being described as the residual left from removal of a lower-melting fraction (about 20-30%). Little data is given on the palm mid-fraction, except for broad ranges of IV and dilatation values at several temperatures. It is indicated in the patent that a purpose of the development thereof was to produce a product suitable for hot climates, and for this purpose the sal fat fraction is described as being harder than cocoa butter at all temperatures up to the melting temperature (about 39.degree. C.) of cocoa butter.
U.S. Pat. No. 4,157,405 also discloses preparing a blend of refined sal fat with a refined palm oil for the purpose of producing a cocoa butter equivalent, but said sal fat is not fractionated. Further, the palm oil component is described as refined, having an IV of 47 to 54, suggesting the absence of fractionation of this component as well.
For purposes of the present application, a cocoa butter "equivalent" hard butter is one which is compatible (bloom-resistant) with cocoa butter in confectionery applications at a level up to about 60 weight parts of such "equivalent" per about 40 weight parts of cocoa butter, a so-called "total replacement"; or, in some instances, the "equivalent" can take the place entirely of cocoa butter. Even at such levels, the cocoa butter "equivalent", blended with cocoa butter or by itself, must be capable of being tempered by well known procedures for tempering cocoa butter into its most stable polymorphic form, thereby resisting bloom formation.
Despite the desire in the past to closely simulate, in hard butter, the triglyceride structure of cocoa butter, it has been impossible to do more than arrive at an approximation of such structure with greater or lesser detrimental effect, depending upon the source of fats used.
Part of the reason for this is that the triglyceride groups POP, SOS, and POS, as mentioned, make up nearly 80% of the available glycerides, but the remaining 20%, a mixture of glycerides, very significantly affects the properties of the cocoa butter. It is not known what effect each of the several such glycerides have on the properties of cocoa butter, other than collectively.
Attempts have been made to synthesize the POP, SOS and POS groups and blend them in the desired ratio, but without the ability to duplicate the remaining 20% such attempts have resulted in failure.
In addition, by the use of blends of natural fats, it has never been possible to exactly duplicate the POP, SOS, POS ratios of cocoa butter. For instance, in the case of "Coberine", described in U.S. Pat. No. 2,975,060, the POS content is 15-16% compared with nearly 40% of this group in cocoa butter.
The result is that it is totally empirical and adventitious to arrive at a hard butter blend of fats which is an excellent equivalent for cocoa butter. The present invention represents just such a fortuitous and adventitious discovery of such equivalent fat.